This article provides a review of brain tissue alterations that may be detectable using diffusion magnetic resonance imaging MRI (dMRI) approaches and an overview and perspective on the
modern dMRI toolkits for characterizing alterations that follow traumatic brain injury (TBI). Nonin-vasive imaging is a cornerstone of clinical treatment of TBI and has become increasingly used for preclinical and basic research studies. In particular, quantitative MRI methods have the potential to
distinguish and evaluate the complex collection of neurobiological responses to TBI arising from
pathology, neuroprotection, and recovery. dMRI provides unique information about the physical
environment in tissue and can be used to probe physiological, architectural, and microstructural features. Although well-established approaches such as diffusion tensor imaging are known to be highly sensitive to changes in the tissue environment, more advanced dMRI techniques have been
developed that may offer increased specificity or new information for describing abnormalities.
These tools are promising, but incompletely understood in the context of TBI. Furthermore, model dependencies and relative limitations may impact the implementation of these approaches and the interpretation of abnormalities in their metrics. The objective of this paper is to present a basic
review and comparison across dMRI methods as they pertain to the detection of the most commonly observed tissue and cellular alterations following TBI.